The Nutritional and Economic Potential of Vegetables

The green revolution -- the post World War II movement that enhanced crop yields with improved seeds and farming technology -- dramatically increased staple grain production in Asia and Latin America. From 1975 to 1985, maize, wheat and rice production grew twice as fast as the global population, and today these three grains make up nearly 70 percent of today's food supply. But the green revolution had little impact in sub-Saharan Africa, the region most crippled by hunger. In addition, the green revolution has largely ignored vegetable crops, a key component of a healthy diet.

However, an abundance of staple crops will not nourish Africans who are without sufficient access to vegetables, which contain necessary micro-nutrients for a balanced diet. The International Food Policy Research Institute predicts an 18 percent rise in the number of malnourished children in sub-Saharan Africa from 2001 to 2020. Vegetables are also necessary in a meal to make staples palatable. Traditional dishes in the region include both grains and vegetables, and indigenous vegetables are often grown or collected at the household level. But while staples such as rice, maize, wheat and cassava have been the focus of much research and investment, research on vegetables has been severely underfunded.

In 2002, research centers under the Consultative Group on International Agricultural Research (CGIAR) invested $118 million in grains research. In the same year, CGIAR researchers invested only $15.7 million on researching fruits and vegetables.

"Micro-nutrient deficiencies, including lack of Vitamin A, iron and iodine, affect some 1 billion people and are extremely common among rural and urban populations in sub-Saharan Africa," says Abdou Tenkouano, author of a chapter titled "The Nutritional and Economic Potential of Vegetables" in Worldwatch Institute's recently released book, State of the World 2011: Innovations that Nourish the Planet. "[Micronutrient deficiencies] lead to poor mental and physical development -- especially among children -- and cause poor performance in work and in school, further crippling communities already facing other health problems and poverty."

Nourishing the Planet found that researchers, nongovernmental organizations and farmers are rediscovering traditional diets and improving the availability and cultural acceptance of nutritious indigenous vegetables -- like moringa and lablab. They are reigniting interest in traditional vegetable dishes and teaching consumers how to cook them.

"In contrast [to staple crops], vegetable crop species have shorter cycles, are faster growing, require little space, and thus are very dependable," says Tenkouano. "Vegetables are the sustainable solution for a diverse and balanced diet."

Organizations like the World Vegetable Center (AVRDC) and the International Development Research Centre are listening to communities by holding periodic workshops, conferences and field days to bring farmers, consumers and businesses together to find varieties of onion, tomato, eggplant and okra that people actually prefer. Researchers can then develop more nutritious and well-adapted varieties that enhance and complement local dishes.

The seeds of preferred varieties of vegetables are being made more widely available, with improvements in quality. In Tanzania, for example, the World Vegetable Center developed new tomato varieties with higher yields and thicker skins that make them less vulnerable to pests and transport damage.

Many indigenous vegetables are often thought of as weeds, even though they are a vital source of nutrition for millions of people. They have largely been neglected by agricultural research and investment, despite their widespread consumption and cultivation in home gardens. But they are regaining attention, and dormant culinary traditions are being revived.

Researchers have developed improved lines of amaranth, African eggplant, African nightshade, and cowpea, for example. Among others, Slow Food International is reigniting community interest in indigenous vegetables dishes, and AVRDC is teaching consumers how to cook different varieties. Africans are once again realizing how much better indigenous vegetables can taste--and how much less fuel and cooking time is needed to cook them.

As a crop, native vegetables are often more hardy, drought-tolerant and resistant to pests and disease than non-natives, making them a more resilient option for vulnerable small-scale farmers. There is a reduced need for irrigation and expensive chemicals, making them even more accessible to the poorest farmers.

As Africa works to tackle persistent hunger and poverty, it must do so amidst unprecedented population growth, resource depletion and climate changes. Expanding the research and development of vegetable crops could help African communities improve health and incomes while sustainably managing the environmental resources they depend on. As Abdou Tenkouano puts it, the continent needs a revolution of greens.